Update AGENTS.md file

AGENTS.md

@@ -121,6 +121,12 @@ configured and difficult to re-stabilize.
 
 ### Always do these:
 
+- **ALWAYS update `AGENTS.md` when your work changes anything documented here** —
+  architecture, file paths, new files, Payload config, known issues, workflows. Do
+  this in the same task, not as a follow-up. The intro says this too but it bears
+  repeating as a hard rule: the next agent reads this file first and will be misled
+  by stale information.
+
 - **ALWAYS use `bun typecheck` to validate your work**, never `bun build`. Typecheck
   is fast and sufficient. Build is slow and for production deployments only.
 
@@ -531,9 +537,11 @@ packages/backend/
 │   ├── auth.ts                # Auth setup + all user-related functions
 │   ├── crons.ts               # Cron jobs (commented examples)
 │   ├── files.ts               # File upload/storage
+│   ├── globals.d.ts           # Types process.env for Convex backend env vars
 │   ├── http.ts                # HTTP routes (auth only) — DO NOT TOUCH
 │   ├── schema.ts              # Database schema — the source of truth
 │   └── tsconfig.json          # Convex-required TS config
+├── eslint.config.ts           # ESLint config for the backend package
 ├── scripts/
 │   └── generateKeys.mjs       # RS256 JWT keypair generator for Convex Auth
 └── types/
@@ -547,6 +555,19 @@ structure. When `bun typecheck` runs from the repo root, it will print TypeScrip
 output for `@gib/backend` (because there's no valid project to check). This is
 expected and not an error.
 
+**Note on `globals.d.ts`:** The Convex runtime supports `process.env` for reading
+environment variables set in the Convex Dashboard. Because the Convex tsconfig does
+not include `@types/node`, `process` would otherwise be untyped. `globals.d.ts`
+declares `process.env` with the specific variables this backend uses. If you add a
+new env var to the Convex backend, add it here too so TypeScript and ESLint are happy.
+
+**Note on `convex/utils.ts`:** This file may be regenerated by `convex dev` as a
+Convex CLI utility scaffold. It contains `missingEnvVariableUrl` / `deploymentName`
+helpers that reference `CONVEX_CLOUD_URL` — a Convex Cloud concept irrelevant to this
+self-hosted setup. If the file reappears, you can safely delete it (nothing in the
+codebase imports it) or leave it — it won't affect runtime behaviour since the
+functions are never called.
+
 ### Schema design — always extend `users` directly
 
 The preferred and enforced approach in this repo is to **extend the `users` table
@@ -825,6 +846,14 @@ Current state of the template:
   content is partial or missing fields
 - live preview works by loading `/` with `?preview=true` and rendering
   `RefreshRouteOnSave`
+- `payload.config.ts` sets `serverURL: env.NEXT_PUBLIC_SITE_URL` — required for
+  Payload to construct absolute URLs in the admin UI and live preview
+- `get-landing-page-content.ts` only calls `noStore()` when `isPreview` is true —
+  normal (non-preview) requests are cacheable by Next.js. Do not add `noStore()`
+  back unconditionally.
+- `apps/next/src/app/(frontend)/page.tsx` wraps the Payload fetch in a try/catch and
+  falls back to `defaultLandingPageContent` if Postgres is unreachable — the landing
+  page always renders even when the CMS is down
 
 If you need a deeper walkthrough, read `docs/payload-cms.md`. That file should stay in
 sync with the actual Payload implementation in this repo.